Hank Williams Jr. was among the first country singers to wholeheartedly embrace Southern rock, not just nodding to it in his songs, but making it a combustible element of his sound. He recorded the Allman Brothers’ “Come and Go Blues” early in the Bocephus stage of his career, for his 1979 watershed album Whiskey Bent and Hell Bound. The moody ballad was written by Gregg Allman, who died May 27th at age 69.

“Gregg and I have been friends for decades and even toured together a few years back,” Williams tells Rolling Stone Country, recalling their joint 2013 tour. “His music has and will stand the test of time and will live on forever.”

William also cut Allman’s iconic “Midnight Rider” for 1983’s Man of Steel LP, further reinforcing his Southern rock tendencies with one of the genre’s signature songs.

“We lost another great that will now join the angel band,” says Williams.

Since Allman’s death on Saturday, tributes have been streaming in from the country-music community. Eric Church and Lady Antebellum both covered “Midnight Rider” during their concerts this weekend, and Blackberry Smoke’s singer Charlie Starr offered that Allman was “simply the greatest in his field.”

Allman “passed away peacefully at his home in Savannah, Georgia,” a statement on the singer’s website read Saturday. “Gregg struggled with many health issues over the past several years. During that time, Gregg considered being on the road playing music with his brothers and solo band for his beloved fans, essential medicine for his soul. Playing music lifted him up and kept him going during the toughest of times.”